The nature of the alkoxide group, solvent, catalyst, and concentration on the gelation and porosity of hexylene-bridged polysilsesquioxanes
Bibliographic record
Abstract
Hexylene-bridged polysilsesquioxanes are hybrid organic-inorganic materials prepared by the sol-gel polymerization of 1,6-bis(trialkoxysilyl)hexane monomers: (1) R = Methyl; (2) R = Ethyl; and (3) R = n-Propyl. Previous studies showed that high surface area xerogels could be prepared from 2 with base catalyzed polymerizations while non-porous xerogels could be prepared with acidic catalysts. The object of this study was to ascertain the influences of monomer alkoxide group, solvent, catalyst, and monomer concentration on gelation time, and the properties of the resulting xerogels.This study has provided some insight into the chemical parameters that affect the ultimate structure in bridged polysilsesquioxanes. First, gelation times do not necessarily directly reflect the hydrolysis and condensation rates expected for different alkoxide groups. The collapse of porosity during the drying of hexylene-bridged polysilsesquioxanes occurs in nearly all acid-catalyzed samples, save those that form quickly due to concentration or from the methoxide monomer 1 in methanolic solution. This suggests that there may be a kinetic contribution to creating porosity in addition to the network compliance model. It would also appear that syneresis of gels during aging may be the symptom of changes resulting in increased porosity. Whatever these changes may be due to, they do not appear to significantly alter the structural composition. Experiments are underway to provide more information and test some of these hypotheses.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".